CONTENTS

I [An Appeal for Aid]
II [Explanations]
III [A Face at the Window]
IV [Tom's Experiments]
V [Mary's Present]
VI [Mr. Nestor's Letter]
VII [Off for Peru]
VIII [The Bearded Man]
IX [The Bomb]
X [Professor Bumper]
XI [In the Andes]
XII [The Tunnel]
XIII [Tom's Explosive]
XIV [Mysterious Disappearances]
XV [Frightened Indians]
XVI [On the Watch]
XVII [The Condor]
XVIII [The Indian Strike]
XIX [A Woman Tells]
XX [Despair]
XXI [A New Explosive]
XXII [The Fight]
XXIII [A Great Blast]
XXIV [The Hidden City]
XXV [Success]